Automobile-kitchen.



W. C. MERRILL.

' AUTOMOBlLE KlTCHEN.

APPLICAHON mu) MAY12.I915.

Patented Nov. 19, 1918.

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UNITED STATES PATENT OFFICE.

WILLIS O. WILL, O1 BOSTON, KASS AOHUSET'IS, ASSIGNOB, BY HESHE' ASSIGN-MENTS, TO THE MERRILL CORPORATION OI KASSACHIJSETTS.

PROCESS COMPANY,

or nos'ron, nassacnusm'rs, a

an'rononrtn-xncnnn.

To all whom it may concern:

Be it known that I, Wmas C. Manama,

- of Boston, in the county of Suffolk and State from 300 F. to 400 F.more or less as desired, ma be used without danger of pressure, as t eonly pressure present in my apparatus is a pressure due to the frictionof a'circulating fluid or circulatin oil heating medium travelin throughthe plpes through which the heat is radiated for the cooking purposes,and not due to the temperature of the circulatin heated fluid medium.

This hea circulating fluid medium kept in constant circulation producesa uniform temgierature throughout the oven which may be ormed of severalindependent compartments or contain utensils adapted for separate orindependent uses, and circulates through a continuous conduit. The-lossby its use is negligible, and for this reason it may be used with greateconomy in the op-- eration of the oven over the use of coal and coke asat present where the heat generated after being utilized to some extentp into the ear and is not continuously utilized.

This circulating heating fluid medium, which may be a mineral 011 havinga high flash point, permits the raising of the tanperature of thiscirculatin eating fluid medium to a temperature yond t at required toheat the ovens to accomplish the objects desired, namely, the cooking offood roducts, that is, such as roasting meats, aking bread, cookingbeans or soup or performing any of the necessary acts inthe culinaryart. 4

An additional advantage in the use of this circulating heating fluidmedium is the facility of producing variable temperatures to meet thedifierent needs in coo 'ng of va- Wou new: new. Application flied 11118, 1015. term No. 27,548.

out my invention 'I employ a mechanism of the automobile. .oil is forcedthrough the pipe Patented Nov. 19,

. rious articles, and at the same time is under immediate control andmay be easily regulated by} the attendant.

In t e accom an draw which illustrate p ymg mgs vention:

Figure 1 is a side elevation partly in section of iny'improved portableoven mounted on an automobile tion.

Fig. 2 is a rear end view of the oven.

Fig. 3 is a, plan view through the compartments of the oven.

"Fig. 4 is a detail view of the thermostatic device.

truck with parts in seca construction embodying my in- Like letters ofreference refer to like throughout the views.

A is an automobile truck of any desired construction on which is mountedthe body" B provided with a seat C for the driver.

Atthe rear end of the truck there is carried the oven consisting of theseparate 00, partments D, E and F having respectiv y the upper and lowerdoors G, g, H, h, I, a, on o posite sides of the oven, see Fig. 2, and trough which doors the food for cooking may be inserted and removed atthe proper times. Suitable shelves K (see Fig. 3) ma be located in thecompartments D, E, and to provide extra spaces for the materials to becooked.

The oil used for heating is furnished through the sup lytank J and drawnthrough the ipe to the pump L which is driven by t e chain M from thedriving This heating N coiled at O in the heater W and asses from theheater to the feed pipe P mm which lead threebranch pipes a, c and e toa series of hollow pipes forming grills S, T and U respectively in thecompartments F, E and D respectively. These branch pi es 0., c and e areindependently controlled the hand valves b,d and f, so that the circuating heat- L. Any one or more of these compartments may be heated asdesired by manipulating the hand valves 1), d and f.

The pipe P beyond the branch pipe 1 1S controlled by a valve is andcontinues to the hollow bearing 0 and if the valve In is opened thecirculating heating oil passes into the jacket m of the soup tureen nand out through the opposite hollow bearing 1) down through the pipe 1'to the pipe V and thence to the pump L. The heater W receives its supplyof fuel from the supply tank 1 through the pipe 2 leading to an ordinaryatomizer burner R and this tank 1 is put under air pressure from time totime b operating the handle 3 of the air pump d which air pressurepassing through the pipe 9 forces the liquid fuel from the tank 1through the pipe 2 to the atomizer R located in the heater W from whichheater the prodnets of combustion pass off in any desired manner.

By employing forced or rapid circulation of the heating fluid medium itis possible to use high temperatures in the heater W where thecirculating heating fluid oil medium is heated, thereby insuring greateconomy, as the heat units generated by the burning liquid fuel areabsorbed and transferred to the ovens b the circulation of thecirculating heating uid medium.

This heating circulating medium is capable of withstanding a temperatureof 400 F. more or less without carboniz'ing so that the temperaturenecessary in the cooking of the materials, such as roast and bread,reaches a proper degree, that is, in the case of roast about 400 F.,before the circulating heated oil reaches a degree where it would beginto deposit carbon, if it contained any such material, upon the interiorof the heating coils and thus prevent the free radiation from thecirculating heating oil of the heating device to the severalcompartments of the oven so that the pipes on the inner service remainfree from deposits of carbonizing material which would materiallyinterfere with their conductivity of heat to the oven where the articlesare being cooked.

This circulating heating oil has the advantage over steam of reaching ahigh degree of temperature without pressure excepting a negligiblepressure, say 5 to 10 lbs. per sq. in. due to the friction of thecirculating oil through the ipes and not" due to pressure from anyga'sification of the heating oil circulating through the heating pipesor coils andalso avoids the necessity of steam tight joints which arenecessary where high pressures are used which should be the case wheresteam Was raised to the temperature necessary to radiate heat at such atemperature as to cook roast, that is about 400 F. The supply tank J forthe circulating heating oil also acts as the expension tank to take careof this pressure, which being low as above stated obviates the necessityof supervision and constant attendance, which would be the case in theuse of steam, if safety is to be considered. The pressure beingnegligible, no extra provisions are necessary, as in steam heatedapparatus, and attendance is reduced to a minimum.

A distinctive feature in this system is the storing of the heat in theliquid fuel and not requiring a storage capacity in the oven, as is nowrequired in ordinary ovens with tile or cast iron as a lining forstoring the heat. And further in this system the regulation of theheating means is capable of easy con trol which is not the case wheredirect fire is used which is not susceptible of such control.

In this system the heat is generated exterior and apart from the ovenand is transmitted through a closed conduit by radiation into a closedinsulated chamber through which no open drafts are maintained and theresult is greater economy in operation and better results in the cookingbecause of freedom from movement of the heated air through the chamberor chambers. and also the chamber or chambers being selfcontained escapeof odors is lessened. The heat losses are very slight, as the oven isinsulated and no loss or escape takes place, as the chamber or chambersof the oven have no direct draft or outlet as is required to keep thefires in ordinary ovens in operation to sustain combustion.

In this system there is a further advantage of an even sustainedtemperature, which is possible, as no replenishing of fuel is necessarywithin the oven. There is no appreciable loss to the heat circulatingfluid medium, as the temperatures are not raised high enough to gasifymaterially the circulatin heating fluid medium, and as long as thecirculating heatin fluid medium is sus tained at the require temperatureby the heating liquid fuel in the heater, there is a continuous supplyof heat to the chamber or chambers of the oven at a predeterminedtemperature, for instance, for roasts about 400 F., cake about 400 F,bread about 350 F., beans about 300 F. and so on for various otherarticles of food which may be cooked in this system.

. When steam or indirect heatin is employed for bread baking theoperation is extremely long, as the temperatures obtained, without unduepressure, are too low to accomplish the desired results quickly.

In the continuous circulation of this heating fluid medium, the lossesusually attendant upon circulating steam do not occur, the loss beingnegligible in this circulating heating fluid medium, as condensationdoes not take place and the absorption of the heat units imparted to thecirculating heating fluid medium are given up directly when brought incontact with the material to be heated. No provision in this system ofcirculation is necessarily provided as with steam to dispose of thecondensation. In the use of this circulating heating fluid medium thereis no renewal of the circulating heating fluid medium and no supply hasto be furnished like the water supply when steam is generated.

An automatic thermostatic device may be located in the circulating pipeN and control a valve in the pipe 2 so that the liquid fuel supply tothe burner R in the heater IV would be shut off when the temperature ofthe circulating heating fluid medium in the pipe N reached apredetermined fixed point. say 420 F., by the spring 4 expanding andmoving the rod 5 to close the valve 6 in the fuel supply pipe 2. Similarindependent automatic thermostatic devices may also be arranged for eachof the chambers D, E and F and also the soup tureen a so that thecirculating heating fluid medium flowing through the pipes u, c and cand the hollow bearing 0 may be independently cut off at a predeterminedfixed temperature by independent thern'iostatic devices provided foreach heating compartment or utensil: in each case the thermostaticdevice being set at the proper degree for the food under treatment. Theautomatic thermostatic device t in the pipe N controlling the valve (3would be set at a predetermined. temperature higher than thethermostatic devices for the chambers I). E and F and soup tureen a, sothat there would be a flow of the circulating heating oil to thatchamber requiring the highest degree of heat or temperature before theli uid fuel supply was cut off through the pipe 2 upon a rise intemperature of the circulating heating fluid medium in the pipe N abovethe temperature at which the thermostatic device 4 is set to operate inthe pipe N.

In practice by this system no material loss of this circulating eatingfluid medium of high boiling point occurs, as the temperature at whichvaporization would take place is not approached and the circulatingheating fluid medium being a nonelaatic liquid difi'ers from acondensable elastic fluid like steam and may be used over and over againfor heating the material under treatment.

I do not limit myself to the arrangement and construction shown, as thesame may be varied without departing from the spirit of my invention.

Having thus described the nature of my invention and set forth aconstruction embodying the same. what I claim as new and desire tosecure by Letters Patent of the United States, is:

An automobile kitchen comprising a self propelled truck having anoperators station at its forward portion, a series of cooking utensilsarranged along the truck body. a heater mounted at the rear portion ofsaid truck, a pump located between said operators station and saidutensils, a continuous conduit extending through said heater and pumpand adjacent said utensils to supply heat to the latter, viscous liquidfilling said conduit. :1 fluid fuel supply for said heater having a pumplocated adjacent said operators station, and means to maintain a slightstatic supply pressure on said viscous liquid in said conduit.

In testimony whereof I have signed my name to this specification, this10th day of May, A. D. 1915.

WILLIS C. MERRILL.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. C."

